Monday, June 08, 2009

Vauxhall Viva GT road test

From CAR Magazine, April 1968

Vauxhall Viva GT test (by retromotoring)

IN ESSENCE THE VIVA GT IS A big engine in a little body. This is a formula which Vauxhall are coming increasingly to accept, having kicked off with the introduction of the very good Ventora. The big engine they have put in the Viva body is that of the Victor 2000, which has not been left entirely in standard form but has been endowed with a new twin-Stromberg CD induction system and a better exhaust manifold. This gives a useful extra 10bhp at only slightly higher rpm and after what we said about the Victor in February could obviously do with going into the basic car too. Compression ratio is still a modest 8.5 to one which means that the car is not too fussy about the sort of petrol it drinks.

There are plenty of other specification changes to match. The brakes are bigger all round, with a substantial servo unit to make them light as ever to operate. The coil springs have been stiffened, the dampers rerated, the wheels are up from 12 to 13in, and radial tyres are standard with, as an option, new ultra-low profile radials (70percent height/width ratio) such as were fitted to our preview car.

External touches consist of a somewhat boy-racer paint job - shiny acrylic body, matt black bonnet and tail panel, coachwork lines down the sides, GT badges - together with a new grille, two real exhaust pipes and two dummy ones. All a bit overdone, especially after the restraint of the Ventora, even though we were spared the racing-type wheels which are to become an optional extra.

More to the point is what they have done to the transmission. You can do lots of sums if you have a sliderule and the inclination, based on the use of the Victor 2000's 3.9 to one final drive and the presence of a Victor gearbox with first and second gears closed up but third left as it is. All this means that with the red line at 6250rpm the maximum speeds in the gears are 42, 60, 78, 106mph. The last speed is fairly easily obtained downhill and maintained on the level despite being well past the power peak, which leads one to the instant conclusion that the car is undergeared. At the same time we can take the speeds at peak power (5000rpm) as representing sensible change-up points for fairly sporting driving and arrive at 36, 52, 67, 92mph. Observe the jump of 16mph from first to second, only 15mph from second to third, but 25mph from third to top, giving us the further instant conclusion that as in the Ventora, third gear is too low and the car is a Barbara Castle special, God help us all.

Given a free choice of ratios we would first up the final drive to 3.6 (giving 45/65/85/115 at the red line) and secondly up third gear from 1.35 to 1.25 which would make that 85 into 92. We would have thought the least Luton could do in the meantime is offer an overdrive. Apart from all else this might help to keep down the oil and water temperatures which seemed to run high on most of the preview cars when driven hard on a fairly cold day. Inside, the car is very pretty with all necessary dials -including the rarely seen oil temperature gauge - and a leather covered steering wheel. The finish is matt black throughout, and it is all very nice except that the seats are apparently standard Viva SL (small, bouncy, with non-adjustable squab) and the front ones don't go far enough back for a tall driver. For this reason it is possibly a good thing that the little steering wheel is too high, for such a driver would otherwise have to splay his legs on either side of it to get at the pedals. Headroom is minimal as always, but the seat belts are now better placed and there are new, easily-reached safety catches for the front seats, showing that at least the Vauxhall people are capable of appreciating the need for change.

From Luton we ran down the M1 for a bit, and one or two faults began to manifest themselves. The tachometer and speedometer were clearly not to be trusted to any extent in our car. and there was occasional fluffing at high speed in top gear which felt for all the world like fuel starvation caused by insufficient pump capacity. The noise level was very high. Pat Kenning, our compatriot from Motor Trader, had a portable noise meter which clocked 82dbA at an indicated 60mph, and no less than 94dbA at an indicated 90, which is really way beyond a joke. With people acting all gormless on the bit of the motorway reduced to two lanes by road works, we soon found that the horn was the feeble, polite little one out of the ordinary Viva.

Things got better once we were flicking our way down our favourite twisty B road, grateful for the crushing overtaking performance when overtaking the odd mimser but still wishing for a higher third gear to eliminate the need for a certain amount of rowing between third and top. The car was very stable- it was arrow-straight when hands-off on the motorway - and felt like a classic understeer, very nice on fast, open bends but a bit unhappy at the back end when cornering over broken surfaces. A few attempted standing starts were un-impressive, because the massive grip of the squat radial tyres on the dry road killed the engine rather than permit wheelspin. The brakes felt a bit rough when used hard (most likely due to a disc imperfection peculiar to our car, we thought) and ended up by smelling quite a lot but never showed any other sign of fade or physical distress.

Then we came to one of our most favourite tight corners, taken left-handed. Feeling confident by now, we threw the car at a point inside the apex of the bend, let the understeer take charge, and then crammed on the power at the apex and waited for the tail to tuck downwards and the handling change to neutral to let us pick the best line out, just as it does in the Ventora with its impeccable balance. But no; the tail stayed right where it was, and the front wheels ran wider and wider. Most of the way round and about to hit the right-hand verge we eased off the accelerator. As if it suddenly realised why we had all that lock on, the car whipped back across the full width of the road and we only just held it before hitting the left-hand verge.

Recover. Deep breath. Go back and look. There on the road are three black lines, one of them a wide smear starting at the apex. Oh dear. One of us tries again, a little more trepidly; the other watches. As the power goes on the inside front wheel rises into the air, the outside front tyre runs more on its sidewall than its tread, and there we have clear, dramatic understeer. The real trouble is obviously that the back end is just too damned well located, an excellent thing with 50bhp 4 under the bonnet but less so with 100. The sort of thing which should not be beyond a cure: what it is like in the wet we shall have to wait and see.

Meanwhile we go to a garage and push up the tyre pressures. Trying again, and with the benefit of experience, we can follow the understeer turning to oversteer and pin it down with reapplication of power at the neutral steer stage. But the beast still runs wide and it is not a trick we would recommend most people to try... and we are sorry about all that rubber on the road citizens.

So there is the Viva GT. Nothing like a true GT car, unlike the Ventora which with a bit of work could become one, it is nevertheless a pretty little fun car which could become even better with assiduous development. At the moment £1022 is a bit much to be asking for a car which is excessively noisy, wrongly geared, has a poor driving position if you are at all big and displays some tricky handling in tight situations. But then Vauxhall seem to have this ability to learn and put right...

Inevitably comparisons will be drawn with the Escort Twin Cam, and the main features of both have been outlined at the bottom of this page as a sort of aide-memoire. The Viva GT is clearly slightly different in concept in that it relies on an engine which, while much bigger than standard, is still not far from being a stock unit, while the big-bore Escort uses the specialised and inevitably more expensive engine from the Lotus Elan/Cortina Twin Cam. Thus it will probably be easier to get the Vauxhall engine properly looked after, although in terms of outright reliability the Ford engine is unlikely to be any the worse off, having largely recovered from its early maladies, real and imaginary.

The comparison suggests that the two cars will be different enough to sell to slightly different market sectors, but there is bound to be a considerable degree of overlap. lt would probably not be unfair to say that the Escort is more likely to be bought by those who are serious about their motoring, if only because they cannot but help being impressed by the whole-hearted way that Ford are putting their car through its competitions programme. lt may well be that GM can sell performance-image cars in the US without having to actually go racing or rallying, but it is difficult to see the same thing happening here to the extent that Vauxhall would like. Apart from all else Fords competition work will mean that any snags are liable to be more quickly found and the solutions more thoroughly developed. This competition thing, you know; it jolly well works...

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